The present invention relates to a new and distinct cultivar of carpet bugle that is grown for use as an ornamental groundcover for the landscape. The new cultivar is known botanically as Ajuga reptans and will be referred to hereinafter by the cultivar name ‘Black Scallop’.
For approximately eight years prior to the selection of ‘Black Scallop’ as described below, the inventor had grown for sale as one year old plants the dark-leaved Ajuga reptans variety known as ‘Braunherz’ (unpatented). In common with inventor's commercial practice, in order to obtain and maintain a reliable source of clean stock plants of ‘Braunherz’, the inventor had established plants of ‘Braunherz’ in vitro in the inventor's nursery laboratory. In 1998, the inventor observed a single plant within a batch of plants that had been grown in pots in soil-based medium from the inventor's in vitro ‘Braunherz’ material. This single plant, ‘Black Scallop’, was a naturally occurring whole plant mutation that exhibited novel and attractive foliage characteristics which the inventor considered set it apart from ‘Braunherz’ and from other varieties of Ajuga known to the inventor. The inventor isolated, and in 2000 first asexually reproduced ‘Black Scallop’ using basal shoot cuttings. All of the resulting plants were grown to maturity and the inventor determined that ‘Black Scallop’ had remained stable and true to type. ‘Black Scallop’ has remained stable and true to type through subsequent generations of asexual reproduction.
‘Black Scallop’ is a perennial ground cover with dark violet flowers and a mat of dark maroon-purple leaves. The parent plant is Ajuga reptans' ‘Braunherz’ which is considered by the inventor to be the closest comparison plant to ‘Black Scallop’. The foliage of ‘Black Scallop’ is larger and rounder and more uniformly dark than other medium-sized cultivars of dark-leaved Ajuga known to the inventor, including ‘Braunherz’. The foliage of ‘Black Scallop’ is smaller than the large-sized cultivars of bronze-green-leaved Ajuga known to the inventor, including the cultivar Ajuga ‘Catlin's Giant’ (unpatented) which is typical of the type. When compared with ‘Braunherz’, ‘Black Scallop’ exhibits larger flowers and the whole plant exhibits greater heat tolerance, and greater resistance to powdery mildew.